Piece below drip rail, where the window gasket goes into

[Shmity1]

Sorry, not sure the name of this part so I am not sure how to search for it.

Do I seal this piece to the body of the car and if so, what with?

Thanks

Shmity

[BLK 68 R/T]

Pretty sure this is what you are talking about.

https://www.detroitmuscletechnologies.com/mopar-b-body-66-70-weatherstrip-channel-drip-rail-foam-tape-rolls/

[Shmity1]

Chaching!  That's it!  Thanks a ton.

Shmity